LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Hugh Dickins <hugh@veritas.com>
To: Adam Litke <agl@us.ibm.com>
Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	linux-mm@kvack.org
Subject: Re: [PATCH] Define the shmem_inode_info flags directly
Date: Wed, 7 Feb 2007 23:27:42 +0000 (GMT)	[thread overview]
Message-ID: <Pine.LNX.4.64.0702072320410.3025@blonde.wat.veritas.com> (raw)
In-Reply-To: <20070207204030.30615.77294.stgit@localhost.localdomain>

On Wed, 7 Feb 2007, Adam Litke wrote:
> 
> Andrew: This is a pretty basic and obvious cleanup IMO.  How about a ride in
> -mm?
> 
> Defining flags in terms of other flags is always confusing.  Give them literal
> values instead of defining them in terms of VM_flags.  While we're at it, move
> them to a header file in preparation for the introduction of a
> SHMEM_HUGETLB flag.

NAK.  Look further and you'll find at least VM_LOCKED and VM_ACCOUNT
also used straight in shmem info->flags: it's trying to ensure there
won't be a clash when applying VM_flags there.  So you've a choice of
three ways forward, I don't mind which: (a) leave it alone, (b) add
comments, (c) define a separate set of flags for SHMEM and convert
where necessary.  But NAK to this patch.

(Sorry, I'm way behind and haven't checked your earlier mails yet.)

Hugh

> 
> Signed-off-by: Adam Litke <agl@us.ibm.com>
> ---
> 
>  include/linux/shmem_fs.h |    4 ++++
>  mm/shmem.c               |    4 ----
>  2 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
> index f3c5189..3ea0b6e 100644
> --- a/include/linux/shmem_fs.h
> +++ b/include/linux/shmem_fs.h
> @@ -8,6 +8,10 @@
>  
>  #define SHMEM_NR_DIRECT 16
>  
> +/* These info->flags are used to handle pagein/truncate races efficiently */
> +#define SHMEM_PAGEIN	0x00000001
> +#define SHMEM_TRUNCATE	0x00000002
> +
>  struct shmem_inode_info {
>  	spinlock_t		lock;
>  	unsigned long		flags;
> diff --git a/mm/shmem.c b/mm/shmem.c
> index 70da7a0..a9bdb0d 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -66,10 +66,6 @@
>  
>  #define VM_ACCT(size)    (PAGE_CACHE_ALIGN(size) >> PAGE_SHIFT)
>  
> -/* info->flags needs VM_flags to handle pagein/truncate races efficiently */
> -#define SHMEM_PAGEIN	 VM_READ
> -#define SHMEM_TRUNCATE	 VM_WRITE
> -
>  /* Definition to limit shmem_truncate's steps between cond_rescheds */
>  #define LATENCY_LIMIT	 64

      reply	other threads:[~2007-02-07 23:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-07 20:40 Adam Litke
2007-02-07 23:27 ` Hugh Dickins [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Pine.LNX.4.64.0702072320410.3025@blonde.wat.veritas.com \
    --to=hugh@veritas.com \
    --cc=agl@us.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --subject='Re: [PATCH] Define the shmem_inode_info flags directly' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).